Oxidative and pre-inflammatory stress in wedge resection of pulmonary parenchyma using the radiofrequency ablation technique in a swine model

Protective effect of extracorporeal membrane pulmonary oxygenation combined with cardiopulmonary resuscitation on post-resuscitation lung injury

BACKGROUND

Cardiac arrest (CA) is a critical condition that is a concern to healthcare workers. Comparative studies on extracorporeal cardiopulmonary resuscitation (ECPR) and conventional cardiopulmonary resuscitation (CCPR) technologies have shown that ECPR is superior to CCPR. However, there is a lack of studies that compare the protective effects of these two resuscitative methods on organs. Therefore, we aim to perform experiments in swine models of ventricular fibrillation-induced CA to study whether the early application of ECPR has advantages over CCPR in the lung injury and to explore the protective mechanism of ECPR on the post-resuscitation pulmonary injury.

METHODS

Sixteen male swine were randomized to CCPR (CCPR; n=8; CCPR alone) and ECPR (ECPR; n=8; extracorporeal membrane oxygenation with CCPR) groups, with the restoration of spontaneous circulation at 6 hours as an endpoint.

RESULTS

For the two groups, the survival rates between the two groups were not statistically significant (P>0.05), the blood and lung biomarkers were statistically significant (P<0.05), and the extravascular lung water and pulmonary vascular permeability index were statistically significant (P<0.01). Compared with the ECPR group, electron microscopy revealed mostly vacuolated intracellular alveolar type II lamellar bodies and a fuzzy lamellar structure with widening and blurring of the blood-gas barrier in the CCPR group.

CONCLUSIONS

ECPR may have pulmonary protective effects, possibly related to the regulation of alveolar surface-active proteins and mitigated oxidative stress response post-resuscitation.

Glomerular Loss After Renal Radiofrequency Ablation Are Comparable to 30 Minutes of Warm Ischemia

PURPOSE

To compare, with stereological methods, the glomerular loss in kidneys submitted to radiofrequency ablation (RFA) or warm ischemia.

MATERIALS AND METHODS

Twenty-six male pigs were divided into three groups. Eight animals were allocated in the sham group, which was submitted to laparoscopic dissection of the left renal hilum, without renal ischemia. Eight animals were allocated in the ischemia group, which had the left renal hilum clamped for 30 minutes under laparoscopic access. Ten animals were submitted to RFA of the left kidney lower pole, under laparoscopic visualization. Animals were euthanized 21 days after surgery, when kidneys were collected. Fragments of the upper pole of the left kidney were processed for morphometric analysis. Right kidney was used as self-controls for each animal. Glomerular volumetric density (Vv[glom]); volume-weighted glomerular volume (VWGV); and glomerular density were quantified by stereological methods and compared by Student's t-test and one-way-analysis of variance with Dunnett's post-test.

RESULTS

Three animals in the RFA group developed postoperative complications (Urinoma/Hydronephrosis) and were excluded from the analysis. No difference was found among the kidneys submitted to RFA and warm ischemia for all parameters. However, these kidneys showed lower Vv[glom] and glomerular density when compared to its self-controls (right kidneys), and when compared to sham-operated animals (p < 0.05). No difference was observed in regards to VWGV among the groups.

CONCLUSION

RFA in pigs determines a significant reduction of glomerular density in the remaining parenchyma. This alteration was comparable to that observed in kidneys submitted to 30 minutes of warm ischemia.

Copper chelation by trientine dihydrochloride inhibits liver RFA-induced inflammatory responses in vivo

OBJECTIVE

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third most common cause of cancer-related death worldwide. Radiofrequency ablation (RFA) is currently performed widely for managing HCC. RFA treatment causes damage around the ablation. Trientine dihydrochloride has been used to reduce the copper in liver.

METHODS

The rats were treated with trientine dihydrochloride for 5 days before liver RFA. Liver function, copper concentration, inflammation biomarkers and MDA, SOD were analyzed after RFA treatment for 2 h, 2 and 5 days.

RESULTS

The results indicated that trientine dihydrochloride reduced the copper in plasma and liver tissue significantly. And trientine dihydrochloride significantly inhibited RFA-induced inflammatory gene expression in liver. Similar inhibitory effects of trientine dihydrochloride were observed on ROS-induced malondialdehyde production in liver tissues.

CONCLUSION

These results suggest that pre-treatment with the selective copper chelator trientine dihydrochloride can inhibit inflammatory response effectively during and after liver RFA in vivo. Chelation of copper to a lower level before liver RFA may be a novel strategy to prevent or ameliorate inflammatory responses in liver induced by RFA and to protect the parenchyma tissues in liver during and after RFA in HCC patients.